Is black jack ok for pregnant women

Hello, Anon! Thank you for writing.

Bidens pilosa (also referred to as blackjack or spanish needles) is a species of flowering plant in the aster family. It's native to the Americas but also known as an introduced species of other regions of the world.  Although this plant is considered a weed in some parts of the world, in other parts it's a source of food and/or medicine, so it's best to check with your doctor before consuming it. 

Helena